I imagine it's more difficult to make it so every one of your different devices (Garmin has an extensive lineup) is able to interface appropriately with every o

I imagine it's more difficult to make it so every one of your different devices (Garmin has an extensive lineup) is able to interface appropriately with every other device than it is to code against a straightforward HTTP(S) server sitting somewhere in the cloud under your complete control. Fits Hanlon's Razor better, too.